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All results from a given calculation for C2 (Carbon diatomic)

using model chemistry: CCSD(T)/cc-pVTZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 1Σg+
2 1 yes D*H 3Πu

State 1 (1Σg+)

Jump to S2C1
Energy calculated at CCSD(T)/cc-pVTZ
 hartrees
Energy at 0K-75.783164
Energy at 298.15K-75.780137
HF Energy-75.401300
Nuclear repulsion energy15.226725
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CCSD(T)/cc-pVTZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Σg 1846 1799        

Unscaled Zero Point Vibrational Energy (zpe) 922.8 cm-1
Scaled (by 0.9748) Zero Point Vibrational Energy (zpe) 899.5 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at CCSD(T)/cc-pVTZ
B
1.79605

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)/cc-pVTZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.625
C2 0.000 0.000 -0.625

Atom - Atom Distances (Å)
  C1 C2
C11.2507
C21.2507

picture of Carbon diatomic state 1 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 (3Πu)

Jump to S1C1
Energy calculated at CCSD(T)/cc-pVTZ
 hartrees
Energy at 0K-75.780294
Energy at 298.15K-75.777264
HF Energy-75.495762
Nuclear repulsion energy14.426683
The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.
Vibrational Frequencies calculated at CCSD(T)/cc-pVTZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
(Å4/u)
Dep P Dep U
1 Σg 1632 1591        

Unscaled Zero Point Vibrational Energy (zpe) 815.9 cm-1
Scaled (by 0.9748) Zero Point Vibrational Energy (zpe) 795.3 cm-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.
Rotational Constants (cm-1) from geometry optimized at CCSD(T)/cc-pVTZ
B
1.61223

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCSD(T)/cc-pVTZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.660
C2 0.000 0.000 -0.660

Atom - Atom Distances (Å)
  C1 C2
C11.3201
C21.3201

picture of Carbon diatomic state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability